Ice eliminating system and oil separator operative therein



D. M. LAWRENCE ICE ELIMINATING SYSTEM AND OIL July 12, 1949.

SEPARATOR OPERATIVE THEREIN 5 Sheets-Sheet l Filed March 51, 1945 :3.25mH. Tal JONFZOU mnammmau NE.:

ZDTrUDW JOKFZOU wroom .n. mEk zA MN pu fw w W l m m S 7 ATTORNEY Julyl2, '1949. v D. M. LAWRENCE 2,476,198

. y ICE ELIMINATING SYSTEM AND OIL SEPARATOR OPERATIVE THEREIN v FiledMarch 51, 1945 5 Sheets-Sheet 2 July 12, 1949 D. M. LAWRENCE 2,476,198

' ICE ELIMINATING SYSTEM AND OIL SEPARATOR OPERATIVE THEREIN Filed March51, 1945 5 sheets-sheet 5 Balla/ld MLuq/reicce July 12, 1949. D, MLAWRENCE 2,476,198

ICE ELIMINATING SYSTEM AND OIL SEPARATOR OPERATIVE THEREIN Filed March31, 1945 -5 Sheets-Sheet 4 10N OUTLET INVENTOR.

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BY l v Patented July 12, 1949 UNITED STATES PATENT OFFICE IC ELIMINATINGSYSTMIAND IL SEPARATOR OPERATIVE THEREIN Dcnaldlvi. Lawrence, Newark, N.J., assignor to'A Bendix Aviation Corporation, Teterboro, N: J2, acorporation of Delaware Application March 31, 1945, SerialNo. 585,941'`15 Claims. 1

The present invention relates to inflatable ice eliminating systems foraircraft and'more'particularly to a novel operating system, oilseparator and air lter for preventing oil, other liquids, and dirt fromentering the'inflatable elements of the system. Such elements arelordinarily composed of rubber and1therefore,-will deteriorate,` ifparticles of oil are permitted to enter the shoes with the-inflating airsupply from the air pump.

An object of the invention is to rprovide a novel electricallycontrolled oil separator and air filter device, particularly adapted foruse with an electrically controlled system such as shown in thecopending application- Serial No.- 498,248, filed August 11, 1943, byDonald M. Lawrence, David Gregg and Myron L. Taylor.

Another objectof the invention is to provide anovel solenoid operatedseparator and lter device.

Another object of the invention is toprovide a novel separator andfilter device so arrangedfthat the device may be. placed in an operativecondition, onlyr at such times as the ice eliminating system is in anoperatingk condition, so as to increase the life f! the lter materialAand reduce the size of the device. Y

Another objectof theinvention is to provide in a compact assemblage anovel oil separator and air filter.

Another object of the invention-is to provide a novel device combining.a solenoid operatedf three way valve, with a pressure controlanda.

combination centrifugal and absorptiontype oil separator having anairandoil discharge passage to an overboard dump.

Another objectv of theinvention is to provide in an oil separator acontrolled discharge air.

passage leading toan overboard dump and'liavn ing provided therein, acheck valve leading from a sump for the separated oil and arranged toallow the oil to bleed to the overboard dump upon the air dischargepassage being closed and saidl ings are forthe' purpose of .illustrationonly, and are not designedias afzdefniti'on" ofthe limits of theinvention, reference being had to the appended claims for' thisIpurpose.

In the drawings:

Figure 1 is a'fragmentary plan View of an aircraft showingdiagrammatically the manner in which the novelair. iilterand' oilseparator is connected into the inat'able; ice eliminating system;

Figure 2` is a sectional View ofthe device taken along the lines 2-f-2ofrligure 3;

Figure 3 is a sectional view of Figure 2 taken along the lines 3+-3 andwith certain parts shown in full;

Figure'flzis' a sectional .view of: Figure 3 takenv along thel lines 4-4with certain parts shown in full.

Figure is an enlarged fragmentary sectional View of theoildischargecheck valve arrangement of Figure.

Referring to the'drawing ofl Figure 1, there is shown an aircraftindicatedv by the numeral I having an engine 2f and inflatable boots 3mounted along the leading edge-of.` the plane as shown, forexample,xin`the `copending application Serial No.498,2485filedAugustf11,,1943, by Donald M. Lawrence, David Gregg and'Myron L. Taylor.

TheV engine 21 isarrangedso as to drive an aircraft propeller 5.Anair'pump 6' is also driven by the engine 2 and has provided a suctionconduit 1 leadingto. the :main suction line. 8 through suitable reliefand check. valves, as; shown.

An air pressure line 9 leads from the pump 'l tothe .inlet ofranoilseparator and'air filter indicated generally` by the numeralv Ill. Theair passes through the device I and during operation of' the iceeliminating system into the outlet conduit I2. During; the passage ofthe air through the device I'ILany,` particles `of Voil which may enterthe air fromzthe pump Ill or other source,.is separated and the air isltered from dirt and other` extraneous matter. The air now thusprocessed,,is-.conducted through the conduit I2 to the main air' pumpline I5.

The main suction and air pressure lines S andIEilead'tosuitable'airdistributor valves i8 which are electricallycontrolled byv a timer indicated generally by the numeralf29-`so as tooperatethe inflatableboot elements 3.2 A plurality of. such distributorvalvesare" preferablyA provided of a type such as-showninrthe aforenotedcc'pending application. The timer 2B may be of the type shown inthelatterrcopending..application or may be of ay type such. as' shownin'vthe. cope'nding application Serial No. 498,250 filed August 1l, 1943,now Patent No. 2,444,208, by Myron L. Taylor, William B. Pond andHerbert A. Eayrs. The operation of the timer is described in detail inthe aforenoted copending applications.

A manually operable switch 25 is arranged to control the operation ofthe timer, as will be readily apparent, through electrical conductors 26and 21 leading from a source of electrical energy 28 while operation ofthe oil separator and air filter I9 is controlled simultaneously throughelectrical conductors 29 and 30.

Thus by closing the switchv 25 the timer 20 and the device I aresimultaneously placed in operation by the closing of the circuits 26-21and 29-30 which control the same. However, when switch is open, thedevice i0 is arranged so as to direct the air flow from the conduit l2to an overboard dump as will be explained hereinafter.

The device I0, as shown in Figures 2, 3, and 4 includes a casing havingatop plate 36 and manifold block 31 mounted thereon. The casing 35 isfastened to a mounting bracket 3B by straps 4l!) and 4|. to the bracket38' by hinged portions 03 and fifi, respectively.

At the opposite ends of the straps 130 and di are projecting ears and45, in which is screw threadedly mounted a fastening screw 03 pro l'jecting through the latter ears and having a nut 139 for securing thestraps lli) and 6| about the casing 35. The supporting bracket 38 hasprojecting arms and 5| which are fastened to the shown in Figures 2' and4. The supporting bracket 38 is also fastened to the manifold block 31by a bolt 56.

The casing 35 has its upper annular end 3l suitably engaged in anannular groove 58 formed in the end plate 36. An opposite bottom portionof the casing 35 is formed by the inwardly and downwardly extendingsides 60. Concentrically fastened in the bottom portion 60 of the casing35 by suitable means is an annular member 6| having an annular recessedportion 63. A second member closes the lower end of the recess 63 sothat the same forms a cup like receptacle for a purpose to be describedhereinafter. A suitable sealing gasket I66 is positioned between themembers 6| and 65 and the members 6| and 65 are conveniently fastenedtogether by screws or other suitable means.

A tubular member 'I0 projects into the member 65 in concentric relationtherewith. Formed within the outer end of the tubular member 19 arescrew threads 1| which are engaged by a screw threaded end of a conduit12 leading to an overboard dump of the aircraft. An annular groove 13formed within the member 05 is adapted to receive an annular sealingring 15 formed of a suitable plastic material such as rubber andconstricted about the tubular member 10.

Fastened at the inner end of the tubular member 10 is one end of asecond tubular member 13. The opposite upper end of the tubular member18 is fastened to a third tubular member 19 which is in turn screwthreadedly engaged at in an opening 8| formed in a recessed portion 85of the top plate 36. The opposite outer end of the tubular member 10 hasa flanged portion 36 which bears upon a sealing ring 81 positioned in arecess 88 formed in the member 65.

Extending from the top plate 36 is a second easing 90 having its upperannular end 92 suit- The straps 40 and 4| are fastened .a

CII

top plate 3c by bolts 54 and 55, respectively, as if.; formed in themanifold block 31.

4 ably engaged in an annular groove 94 formed in the end plate 36. Thecasing 90 is positioned within and in spaced relation to the casing 35and has suitably apertured upper and lower end plates 35 and 96,respectively.

The lower end plate 96 is fastened in position by suitable means, notshown. There is disposed within the casing 90 a filter pack 98 formed ofa suitable material such as cellulose cotton material arranged to absorboil vapor. There may also be positioned in the casing 90 at the upperend of the cellulose cotton material, a suitable layer of activatedcarbon or some other type of vapor absorbing material. There is thusprovided in the casing 90 a filter pack 98 which may be held in positionby the top plate 95. The top plate is fastened in position by a snapsplit ring 98 which engages in an annular groove 99 formed in the casing90.

As shown in Figures 2 and 3, the inner casing 90 and bottom plate 96 arepositioned in space relation to the inner surface of the outer casing 35so as to define a passage between the inner and outer casing indicatedby the numeral |00. The tubular member 1B, moreover, is positioned inconcentric relation to the inner and outer casings 35 and 90 and extendslongitudinally to the upper and lower tubular members 19 and 'i9previously described. Between the perforated top plate 95 and plate 36is provided a chamber |0| which, as shown in Figure 2, opens through aport |02 in the plate 36 into a cored passage |03 formed in the manifoldblock 31. The cored passage |03 opens into an outlet passage |04 Thereis screw threadedly engaged in the passage |04 one end of the pressureconduit I2.

The upper end of the tubular member 19 opens into the recess 85, aspreviously described. There is further formed in the manifold block 31 arecess |05 cooperating with the recess 65 formed in the top plate 36.The manifold block 31 is positioned on a sealing gasket between the topplate 36 and manifold block 31 and is fastened to the top plate 36 bysuitable means.

As shown in Figure 2, the manifold block 31 has an air inlet passage |00in which there is engaged at the screw threads |08, one end of the ,ipressure conduit 9 leading from the air pump 6. An opening ||0 leadsfrom the passage |06 into the recess |05. A second opening l|2 leadsfrom the passage |06 into a recess ||5 formed in the manifold block 31.

As shown in Figure 3, the recess H5 opens l through a cored passage |16into an opening ||1 formed in the top plate 36 and leading into thepassage |00 formed between the inner and outer casings 35 and 90.

Positioned in the passage |00 is an annular ring |20 having formedtherein a series of radial vanes one of which is indicated in Figure 3by numeral |23. The varies |23 project inwardly through slots |24 formedin the ring |20 and are so arranged as to give to the incoming air flowa centrifugal spin for a purpose which will be described hereinafter.

Controlling the ports I I0 and ||2 are ap Valve members |25 and |26. Thevalve member |25 is affixed to one end of a stem |30slidably positionedin an opening |33 formed in an arm |35 which projects from the side wallof the passage |06.

The upper end of the stem |30 is pivotally conr nected at |40 to asecond stem portion |4| to which there is aixed' the flap valve |26.Supporting the flap valve |26 is a 'flexible diaphragm member |45 whichextends across the recess ||5 and is fastened to the manifold block 31by a cap member |41 having a recess |49 cooperating with the diaphragm|45. The cap member |41 is fastened to the manifold block 31 by suitablescrews indicated by numeral |50.

Positioned between the flap valve |26 and the upper inner surface of thecap member |41 is a coil spring |53 which biases the ap valve |26 in adownward direction so as to close the opening I2 and the flap valve |25'in a like direction so as to open the port |0.

A bleed passage |60 leads from lthe pressure inlet conduit |05 to ableed passage 6| opening into the chamber |49 formed at the upper sideof the diaphragm |45. Thus, normally, the superatmospheric pressureexerted through the passage |06 from the pump 6 is applied to thediaphragm |45 at the chamber |49 through the bleeds |60 and |6| so as toaugment the force exerted by the spring |53 andnormally hold the flapvalve |26 closed.

Projecting from the cap member |41 is a casing |65 having heat radiatingfins |66 and housing a solenoid or electromagnet |68 which iselectrically connected through the conduit |69 and connector plug |16with the circuit 29 and 30 previously described with reference to Figure1.

The solenoid |66 controls the movement of an armature fastened to aslidable push rod |16. A pin |18 slidably mounted in the casing |65 andbiased under force of a spring |19 operably connects the push rod to aball valve |80. The ball valve |80 controls a second bleed passage |83opening the chamber |49 to atmosphere. The ball valve |80 is normallybiased under force of spring |85 to a position closing the bleed'passage#63 to the chamber |49. However, upon energi zation of the solenoid |63,the armature |15 is moved downward actuating the ball valve |80 throughrod |16 and pin |18 so as to open the chamber |49 to the atmospherethrough the bleed passage |83. The latter action reduces the pressurewithin the chamber |49 to substantially atmospheric pressure, whereuponthe superatmospheric pressure acting on the under side of the flap valve|26 through the opening ||2 forces the same to a partially openposition. The superatmospheric pressure then acts upon the under side ofthe diaphragm |45 so as to force the flap valve |26 to a full openposition and the flap valve to a full closed position. 'I'he differencebetween the -atmospheric and superatmospheric pressures are suflicientto effect the latter operation. y

There is further provided, as shown in Figures 3 and 4, a valve openingor port |90 leading from one side of the inlet passage |66. A sleevevalve |95 closed at its inner end |96 is slidably mounted in thesupporting member |91. The supporting member |91 is suitably fastened inthe manifold block 31. A coil spring |99 biases the sleeve valve |95 ina direction for closing the valve |90.

The spring has one endengaging the inner end of the sleeve valve l|96while the opposite end is supported by a plate 200. The plate '200 isscrew threadedly mounted on a screw 205 which is rotatably adjustable bya knob 206. The plate 200 is held from rotary movement by a pin 2|0which projects inwardly from the supporting member |91 and into the'plate 2001s.() astopfle'vent rotary movement of the 'plate relativev"to"tl'lepin 2|0,

while permitting longitudinal movement of the plate relative thereto inresponse to rotary adjustment of the screw 205. The latter adjustment ofthe Yplate 200 adjusts the force exerted by the spring |99 so as todetermine the pressure at which the valve will open. As shown in Figure3, a cored passage 226 is formedin the manifold block 31 and leads fromthe passage |90 to a recessed portion '22| formed in the manifold block31. The passage 220 is controlled by the valve |95 and is opened to theport |90 upon the valve |95 being biased to an open position by theforce of the pressure medium inthe inlet passage |06. The recess 22|opens into the recess 85, as shown in Figure 3, so that upon the valve|26 being closed on excess pressure being exerted in the passage H6, the'valve |95 will open releasing such pressure to the atmosphere throughthe tubular member 19 leading to the overboard dump.

In the operation of the above device, it will be seen that uponenergization of the solenoid |63, as upon operation of the inflatableice eliminating system, the nap valve |25 is moved to a closed positionwhile flap valve |26 is opened. The latter operation permits the airentering the passage |06 under pressure of the pump 6 to flow throughchamber ||5 and cored passage ||6 vinto passage |06 where the radialvanes |23 give the air a centrifugal spin tending to separate theparticles of oil from the air. The thus separated oil particles tend todrip down the inner side of the casing 35 and collect in the recessedreceptacle 6|. The air ow, moreover, passes downward and up through theperforated screen 96 into the filter pack 93 where the oil vapors areabsorbed. 'The air then continues to flow upward and through theperforated top plate 98 into chamber |0|. From chamber the air passesthrough passages Iii.' and |03 into outlet passage |06. From passage |04the air flows through outlet conduit I2 to the main pressure conduit i5and through distributor valves |8 to the inflatable ice eliminatingboots 3. Moreover, upon the pressure in the line 9 being in excess of apredetermined value the valve |95 will be biased to an open position andexcess air will pass out through openings |90, 226 and 22|, throughrecess 65 and out tube 18 to the overboard discharge.

The oil which is collected in the receptacle 69 is drained from the samethrough a pin 220 having a passage22| extending longitudinally thereinas indicated "in dotted lines in Figures 3 and 5. The pin 220 is held inposition by an lannular sealing ring 225 formed of rubber or othersuitable material and positioned in cooperating grooves formed in thepin and in the passage in the member 6| in which the pin 220 isinserted. The passage 22| in the pin 220 opens at one end into therecessed portion 63 of the receptacle 6| and at the opposite end into apassage 221. Projecting into the passage 221 and screw ythreadedlyengaged therein at 229 is a valve stem 230.

The valve stem 230 has a passage 233 extending longitudinally thereinand opening at one end into a passage in the member 65 through which theconduit 10 extends. A port 235 opens at the opposite end into radiallyextending ports 231.

A ball valve 239 controls the opening of the portl 235 into the passage233. A spring 238 having one end anchored by a suitable fastening member239A and the opposite end bearing upon the ball valve 239 biases thesame to a position closing the port 235.

"The conduit 10, as shovvn'ih Figures`2'and3,'ha's an annular groove 24Bformed therein and cooperating with the open end of the passage 233.Formed in the groove 240 and opening through the conduit 'l0 areradially extending ports 245 which open into the interior of the passage10.

Through the latter arrangement it will be seen that during the normaloperation of the inflatable ice eliminating system, the oil collected inthe receptacle 6| will be subjected to the normal superatmosphericpressure exerted through passage IGU. The latter pressure will beexerted through the oil in passages 22|, 235 and 231 so as to tend tobias the ball valve 239 to an open position. In the latter position theball valve 239 permits the oil to bleed out through passage 233 andthrough ports 265 into the conduit 10. The oil is then dischargedthrough the conduits 'lll and l2 to the overboard dump.

However, when the solenoid |68 is de-energized as during the period whenthe inflatable ice eliminating system is not in operation, it will beseen that the port |83 will be closed to the chamber |49 through ballvalve |85 and the superatmospheric pressure within the chamber |49 willaugment the biasing force exerted by the spring |53 so as to close flapvalve |2|1` and open flap valve |25. The latter action Will of coursepermit the air under pressure of the pump 6 to exhaust directly toatmosphere through the conduit 'I8 leading to the overboard dump andwill moreover terminate the pressure of the pump t acting throughpassage lii. The ball valve 233 is then biased to a closed positionunder force of the pressure acting through the tube T8 so as to preventany air iiow from backing up through the device l from the dischargetube i8.

lt will be seen that through the latter arrangement, there has beenprovided novel means whereby the only air that will pass through thefilter unit of the oil separator is that air that is actually requiredfor boot operation, thereby increasing the life of the filter material98 and reducing the size and cost of the device I0. Moreover air underpressure of the pump 6 and at an excessive pressure value is releasedthrough the valve |95 prior to its passing through the device i0.Further during the period when the ice eliminating system is not inoperation the air under pressure of the pump l is exhausted directly toatmosphere through the conduit 1B, rather than passing through thedevice lll Although only one embodiment of the invention has beenillustrated and described, various changes in the form and relativearrangements n of the parts, which will not appear to those skilled inthe art, may be made without departing-from the scope of the invention.Reference is, therefore to be had to the appended claims for a denitionof the limits of the invention.

What is claimed is:

1. A device for removing oil from oil ladened air, comprising, incombination, an outer casing, an inner casing mounted within said outercasing and positioned in spaced relation thereto so as to define adownwardly extending air passage between said casings, an air inletconduit, means connecting said air inlet conduit to said rst mentionedair passage, a plurality of radial vanes positioned in said lrstmentioned passage and between said outer and inner casing for impartinga spin to the oil laden air entering said first mentioned passagewhereby the resulting forces are effective to cause the oil to separatefrom the air, a receptaclemounted at the lower end of said outer casingfor collecting the separated oil, said inner casing having air outletpassage means through said inner casing and opening at the upper end ofsaid outer casing, discharge means at the lower end of the outer casing,and valve means alternately operable for discharging said inlet air orsaid separated oil.

2. A device for removing oil from oil ladened air, comprising, incombination, an outer casing, an inner casing mounted within said outercasing and positioned in spaced relation thereto so as to dene adownwardly extending air passage between said casings, an air inletconduit, means connecting said air inlet conduit to said rst mentionedair passage, a plurality of radial varies positioned in said firstmentioned passage and between said outer and inner casing for impartinga spin to the oil laden air entering said rst mentioned passage wherebythe resulting forces are eiiective to cause the oil to separate from theair, a receptacle mounted at the lower end of said outer casing forcollecting the separated oil, said inner casing having air outletpassage means through said inner casing and opening at the upper end ofsaid outer casing, said receptacle having an oil discharge passageextending downwardly from said receptacle, a discharge conduit extendingdownwardly through said receptacle, said oil discharge passage openinginto said conduit, and means alternately operable for discharging saidinlet air or said separated oil through said discharge conduit.

3. A device for removing oil from oil ladened air, comprising, incombination, an outer casing, an inner casing mounted within said outercasing and positioned in spaced relation thereto so as to define adownwardly extending air passage between said casings, an air inletconduit, means connecting said air inlet conduit to said first mentionedair passage, a, plurality of radial vanes positioned in said iirstmentioned passage and between said outer and inner casing for impartinga spin to the oil laden air entering said first mentioned passagewhereby the resulting forces are effective to cause the oil to separatefrom the air, a receptacle mounted at the lower end of said outer casingfor collecting the separated oil, said inner casing having air outletpassage means through said inner casing and opening at the upper end ofsaid outer casing, a discharge conduit extending downwardly through saidreceptacle, and means alternately operable for discharging said inletair or said separated oil through said discharge conduit.

4. A device of the Ycharacter described, comprising, in combination, acasing having air inlet and outlet means, means carried by said casingfor removing oil from oil laden air, receptacle means for collecting theseparated oil, a discharge conduit, and means alternately operable forconnecting said air inlet or said receptacle means to said dischargeconduit.

5. For use in an ice eliminating system for aircraft having aninflatable unit; a device comprising, in combination, a casing havingair inlet and air outlet means, said air outlet means for connection tosaid unit, means carried by said casing for separating oil from oilladen air, a discharge conduit opening from said casing to atmosphere,and valve means carried by said casing and alternately operable forclosing said air inlet means to said separating means or said dischargeconduit.

6. A device ,for removing oil from oil ladened air. comprising. incombination, an outer casing, an inner casing mounted within said outercasing and positioned-'in spaced relation thereto so as to define adownwardly extending air passage between said casings, an air inletconduit, means connecting said air inlet conduit to said rst mentionedair passage, a plurality of radial vanes positioned in said firstmentioned passage and between said outer and inner casing for impartinga spin to the oil laden air entering said first mentioned passagewhereby the resulting forces are effective to cause the oil to separatefrom the air, a receptacle mounted at the lower end of said outer casingfor collecting the separated oil, an air outlet conduit provided at theupper end of said inner casing, air filter means carried by said innercasing for removing oil vapors from said oil laden air in passingthrough said inner casing to said air outlet conduit, a dischargeconduit opening through the upper end of said inner and outer casing andextending downwardly through the lower end thereof, means connectingsaid air inlet conduit to said discharge conduit, and valve means foralternately opening and closing the connecting means for said air inletconduit.

'7. A device for removing oil from oil ladened air, comprising, incombination, an outer casing, an inner casing mounted within said outercasing and positioned in spaced relation thereto so as to define adownwardly extending air passage between said casings, an air inletconduit, means connecting said air inlet conduit to said rst mentionedair passage, a plurality of radial vanes positioned in saidrst mentionedpassage and between said outer and inner casing for imn parting a spinto the oilladen air entering said lrst mentioned passage whereby theresulting forces are effective to cause the oil to separate from theair, a receptacle mounted at the lower end of said outer casing forcollecting the separated oil, an air outlet conduit provided at theupper end of said inner casing, air filter means carried by said innercasing for removing oil vapors from said oil laden air in passingthrough said inner casing to said air outlet conduit, a dischargeconduit opening through the upper end of said inner and outer casing andextending downwardly through the lower end thereof, means connectingsaid air inlet conduit to said discharge conduit, valve means foralternately opening and closing the connecting means from said air inletconduit, and said receptacle having an oil discharge passage from saidreceptacle into said discharge conduit for the discharge of saidseparated oil through said dis-charge conduit.

8. A device for removing oil from oil ladened air, comprising, incombination, an outer casing, an inner casing mounted within said outercasing and positioned in spaced relation thereto so as to dene adownwardly extending air passage between said casings, an air inletconduit, means connecting said air inlet conduit to said rst mentionedair passage, a plurality of radial vanes positioned in said firstmentioned passage and between said outer and inner casing for impartinga spin to the oil laden air entering said rst mentioned passage wherebythe resulting forces are eiective to cause the oil to separate from theair, a receptacle mounted at the lower end of said outer casing forcollecting the separated oil, an air outlet conduit provided at theupper end of said inner casing, air filter means carried by said innercasing for removing oil vapors from said oil laden air in passingthrough said inner Vcasing to said air outletconduit, a dischargeconduit opening through the upper end of said inner and outer casing andextending downwardly through the lower end thereof, means connectingsaid air inlet conduit to said discharge conduit, valve means foralternately opening and closing the connecting means from said air inletconduit, said receptacle having an oil discharge passage from saidreceptacle into said discharge conduit for the discharge of saidSeparated oil through said discharge conduit, and a check valve in saiddischarge passage operable under the air pressure within the firstmentioned passage for opening said discharge passage so as to permitsaid separated oil to bleed from said receptacle into said dischargeconduit upon said connection from said air inlet conduit to said iirstmentioned passage being opened by said valve means.

9. A device for removing oil from oil ladened air, comprising, incombination, an outer casing, an inner casing mounted within said outercasing and positioned in spaced relation thereto so as to define adownwardly extending air passage between said casings, an air inletconduit, means connecting said air inlet conduit to said first mentionedair passage, a plurality of radial varies positioned in said iirstmentioned passage and between said outer and inner casing for impar*-ing a spin to the oil laden air entering said iirst mentioned passagewhereby the resulting forces are effective to cause the oil to separatefrom the air, a receptacle mounted at the lower end of said outer casingfor collecting the separated oil, an air outlet conduit provided at theupper end of said inner casing, air lter means carried by said innercasing for removing oil vapors from said oil laden air in passingthrough said inner casing to said air outlet conduit, a dischargeconduit opening through the upper endr of said inner and outer casingand extending downwardly through the lower end thereof, meansconnectinsY said air inlet conduit to said discharge conduit, valvemeans for alternately opening and closing the connecting means from saidair inlet conduit, said receptacle having an oil discharge passage Afromsaid receptacle into said discharge conduit for the discharge of saidseparated oil through said discharge conduit, a check valve in saiddischarge passage operable under the air pressure within the firstmentioned passage for opening said discharge passage so as to permitsaid separated oil to bleed from said receptacle into said dischargeconduit upon said connection from said inlet yconduit to` said firstmentioned passage being opened by said valve means, and a pressurerelease valve for connecting said air inlet conduit to said dischargeconduit upon -a predetermined air pressure being applied through saidair inlet conduit.

10. For use in an ice eliminating system for aircraft having aninflatable unit; a device comprising, in combination, a casing havingair inlet and air outlet means, said air outlet means for connection tosaid unit, means carried by said casing for separating oil from oilladen air, a discharge conduit through said casing, and solenoidoperated valve means carried by said 'casing and alternately operablefor opening said air inlet means to said separating means and closingsaid discharge conduit or opening said inlet means to said dischargeconduit and closing said inlet means to said separating means.

11. A device of the character described, comprising, in combination, acasing, an air inlet conduit and an air outlet conduit opening into andout of said casing, means carried by said casing for separating oil fromoil laden air, a discharge conduit extending through said casing, and apressure release valve for connecting said air inlet conduit to saiddischarge conduit so as to release inlet air from passing through saidoil separating means upon air pressure in excess of a predeterminedvalue being applied through said air inlet conduit.

12. A device of the character described, comprising, in combination, acasing having air inlet and air outlet means, means carried by saidcasing for separating oil from oil laden air, a discharge conduitthrough said casing, a pressure release valve for connecting said airinlet means to said discharge conduit upon a predetermined air pressurebeing applied at said air inlet means, and separate operator-operativevalve means carried by said casing and alternately operable for openingsaid air inlet means to said separating means and closing said dischargeconduit or opening said air inlet means to said discharge conduit andclosing said air inlet means to said separating means.

13. In an ice eliminating system for aircraft of the class including aplurality of inatable boots formed of a rubber like material and mountedon airfoil surfaces of said aircraft, a pump for providing a source ofsuperatmospheric air pressure, air distributor valves for controllingthe inflation and deflation of said boots, air conduit means forconducting the superatmospheric air pressure from said pump to saiddistributor valves for inating said boots, electrical circuit meansincluding a manually operable switch means for controlling the operationof said air distributor valves, and means for removing oil from the oilladened air from said pump; the improvement comprising an air dischargeconduit leading to atmosphere, means for connecting said dischargeconduit to the air inlet side of said oil removing means, valve meansfor opening and closing said connecting means, and electromagnetic meansfor `controlling the operation oi said valve means, said electromagneticmeans connected in said electrical circuit means and controlled throughoperation of said switch means in such a manner as to close saidconnecting means to said discharge conduit during operation of saidsystem and open said connecting means to said discharge conduit at suchtimes as said system is not in an operating condition.

14. In an ice eliminating system for aircraft of the class including aplurality of inflatable boots formed of a rubber like material andmounted on airfoil surfaces of said aircraft, a pump for providing asource of superatmospheric air pressure for inflating said boots, meansfor removing oil from the oil ladened air from said pump, and said meansconnected between said pump and said boots; the improvement comprisingan air discharge conduit leading to the atmosphere, valve means foralternately connecting the superatmospheric air pressure from said pumpto said discharge conduit or to said boots through said oil removingmeans, electromagnetic means for operating said valve means, and anelectrical circuit means for controlling the operation of said systemand said electromagnetic means, including a switch for manually eiectingsimultaneous operation of said valve means and said ice eliminatingsystem.

l5. For use in an ice eliminating system for aircraft of the classincluding an inflatable boot formed of a rubber like material andmounted on an airfoil surface of said aircraft, and a pump for providinga source of superatmospheric air pressure for inating said boot; adevice comprising in combination a casing, an air inlet conduit openinginto said casing and adapted to be connected to said pump, an air outletconduit from said casing for connection to said boot, oil separatingmeans carried by said casing for removing oil from oil ladened air fromsaid pump, said oil separating means connected in said casing betweenthe air inlet conduit and said air outlet conduit, an air dischargeconduit opening from said casing to atmosphere, and valve means forshifting the connection of said air inlet conduit from said oilseparating means to said air discharge conduit.

DONALD M. LAWRENCE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 343,251 Neracher June 8, 1886581,448 White Apr. 27, 1897 849,641 Sadler Apr. 9, 1907 1,429,713 Cazieret al Sept. 19, 1922 1,499,710 Weisgerber July 1, 1924 1,547,429 LudemanJuly 26, 1925 1,854,010 Woodford Apr. 12, 1932 2,038,039 Gregg Apr. 21,1936 2,174,528 Prentiss Oct. 3, 1939 2,327,046 Hunter Aug. V17, 19432,422,624 Hunter June 17, 1947

